I love these films, when you watch and forget about everything, while getting a whole range of emotions. And the picture does not sag for a second for the entire time.
A thriller is a complex thing, for which not only the plot is important, but also the atmosphere with the characters. Fortunately, we have a powerful primary source here (which I never read). Well, about the other two points, you can not talk. They are in place. I was imbued with the atmosphere of the tape literally from the first seconds. And how depressing the music is. At the same time, the film does not try to jump out of its pants. He just pointedly and exquisitely tells a story that is simple on paper. But this is only on paper.
What's coolest (although some might take it as a minus), it's not piling up the main plot on top of everything. He is, and he is interesting. But the elaboration of the characters (more precisely, two characters) and their dialogues. It's a pleasure to watch this. Hopkins is a genius. In just 16 minutes, squeeze out such a powerful performance that your jaw drops. Really steals every second it appears. What is surprising (although why is it surprising), Jodie Foster breathes down his back all the time, and it's great (well, it's not for nothing that she showed her great acting skills in Taxi Driver). Their tandem is the pinnacle of the film.
This is a movie that you should not advise to watch. Either you have already seen it, or I don't understand why you haven't seen it yet. A sample in its genre. A film in which everything is perfect.